John william smith



(No Model.)

J. W. Smm. DENTAL TOOL.

Patented Feb. 9, 1886.

i f UNITED VSTATES PATENT OFFICE.

JHNWILLIAM sMITH,oE NEWPORT, RHODE ISLAND.

' ADENTAL. Tool..4

SPECIFICATION forming part of Letters Patent No.- 335.780. dated February 9, 1886.

ApplicationfnsaJ-une11,1884; serial-No. 135.166. (No model.)

To all whom it may concern.-

Be it known that I, JOHN WILLIAM SMITH, of the city and county of Newport, and of the State of Rhode Island, have invented a new and useful Dental Tool, of which the following is a specification. 'i

My invention relates to dental tools, beingal spindleor mandrel for use in connection with dental disks and similar tools requiring rotary motion for polishing fillings, separating teeth, and the like.

In practicing the art of dentistry it daily becomes desirable to use tools rotated by the dental engine. Flexible, abrasive, and polish-v I 5 ing disks, commonly made of paper, and more or less coated on one sidewith some gritty substance, are a common class of these-tools.

By the very nature ofthe functions these disks are expected to perform they are necessarily very delicate in 'construction and of limited durability, several disks often being required to finish one filling. It follows, therefore, that the spindle or mandrel by which these disks are revolved should be so'constructed that the disks' may be easily and quickly adjusted in the mandrel, and the latter be also so constructed that it will not be in the way of the operator, or come disagreeably in contact with the teeth or mouth.

The object of my invention is, therefore, to construct ausmall and compact mandrel in which such disks and similar tools can be quickly adjusted and securely -held in place in whatever directionit may be revolved and on whichever side may be the pressure, andas quickly removed and replaced without the use of tools, andwhen broken'or worn out can be replaced at a trifiing cost.

My invention consists of a shaft or spindle teeth, and the inside ofthe head of the pin 5o having a cavity or annular recess sufficiently large and deep to receive said spurs, a sleeve terminating in a flat or concave head or face constructed to slide or screw on Athe shaft, and, when moved near tlie head thereof, adapted to clamp thesections of the clutch and hold the pin rigidly therein, the shaft being slightly 5 5 l Fig. III is a view of the'pin, showing the annular recess in theunder side of its head; Fig. IV, a perspective view ofh'eaded pin; Figi?,l a sectional view of a second form of headed pin; Fig. VI, a'third form of headed pin.

Similar letters of reference referto similar l parts. The shaft A is made at one end to tit into the dental engine or other apparatus for re- 7e f` volving it, the other end terminating in the-- dat or concave head or face-plate B, provided l f4-f with spurs or teeth b. rlhrough the center of the head or shaft, for about threelfourths of an inch in depth from said head, is drilled a, small hole; C. The head end of the shaft is split lengthwise for a distance of about one-half an inch froml the headin two or more sections, leaving between said sections the small spaces e, so as to form a chuck. v

The'head D of the pin d is formed with the annular recess d in its under side, or the under side o'f said head may be concave, or otherwise formed, so as to be adapted to receive, v

pass between, or press against the spurs of 854 the head of the shaft. The shaft'A is slightly beveled for a short distance from its head, as

shown in the drawings, and then the sleeve E is adapted to slide or screw ou saidl shaft, and, when forced upward toward the head of the shaft on the beveled portion thereof, has a tendency to compress the sections of the upper part of the shaft together rand toward the center, which contracts the hole C drilled in the center of that portion of the shaft. v

To fast-en the disk in my improved mandrel,

the pin d is passed .through the center of' the f disk, and then the said pin d is pressed. downv into the hole C in the-shaft till the spurs or teeth b on the head of the shaftare forced into or through the disk. The sleeve E is then slid or screwedoverthe beveled portionl of the shaft', when the sections thereof will be forced of the shaft, `which will release the sections of the clutch and moved. y

Thespurs b are used toprevent the disk from moving around on the pin d, as it would otherwise do; but the spurs by pressing into the disk insire simultaneous rotation of mandrel and dis r. v

The use of the spurs is made necessary from the fact that the pin d is round, and unless some means were employed to require synchronous :movementof mandrel and disk 'the latter would move around on the pin, andthereallow the pin to be easily rezolby be rendered. useless. Their use may, howf ever, he dispensed with by making pin d of any angular or irregular shape to ft into or make for itself an opening of similar shape in the disk it is intended to hold. The pin, however, should always be of such shape, and should it an opening in shaft of such shape, as to practically center the disk when thesleeve Eis removed. I however consider the spurs the best device.

In a dental-disk holder, the combination o thesplit chuck and face-plat e,with spurs and the clamping-sleeve, with a pin fitted to be adjustably clamped in the split chuck, and having a head suitably recessed to inclose the 3 5 spurs ofthe split face-plate, all serving to clamp Iand retain a dental disk, substantially as described. JOHN WILLIAM SMITH.

Vitnesses:

WALTER B. SIMMONS,

EDWIN S. BURDICK. 

